If you’re taking any medication that causes constipation, check with your doctor whether you need to stop taking it.
To do the colonoscopy, your doctor must have a clear view of your colon so it’ll need to be empty. To empty it, the doctor will prescribe bowel preparation medication. The medication normally causes frequent bowel motions, sometimes with stomach cramps and diarrhoea.
Your doctor will have their own specific preparation requirements. These instructions should be strictly followed otherwise the procedure may have to be delayed or repeated.
To prevent dehydration and unpleasant side effects such as dizziness, headache and fainting, you need to drink plenty of water and other clear fluids (e.g. juice, cordial, black tea and coffee, clear soup, jelly and/or sports drinks) while taking the bowel preparation medication.
You’ll probably be advised to follow a restricted low-fibre diet for the last 48 hours before the colonoscopy. You’ll also have to fast for at least three hours before the procedure.